Improvement in builders  jacks



' JOHN F. DARLEY.

lmprm lemen't in Builders Jacks.-

Pfatented May 28,1872.

STATES IMPROVEMENT IN BUILDERS JACKS.

Specification forming part of Letters Patent No. 127,314, dated May 28,1872.

To all whom it may concern:

Be it known that 1, JOHN F. DARLEY, of Nebraska City, in the county ofOtoe, and State of Nebraska, have invented a new and Improved Builders Jack; and I do hereby declare that the following is a full, clear, andexact description thereof, reference being had to the accompanyingdrawing making part of this specification, in which Figure 1 is aperspective view of the jack. Fig. 2 is a view of one side of it. Fig. 3is a section taken vertically and transversely through the platform-beamat the point where the legs are attached to it.

Similar letters of reference indicate correspondin g parts in theseveral figures.

The object of this invention is to construct a jack which will not onlyserve the purposes of the well-known jack for out-door work in a betterand safer manner, but which is also useful for plasterers and all kindsof inside work about buildings. The nature of my invention consists incombining with a platform-bar an adjustable cross-bar and two extensiblelegs or supports, as will be hereinafter explained.

The following description of my invention will enable others skilled inthe art to understand it.

In the accompanying drawing, A represents a horizontal beam, on one endof which aplatform, B, is applied, and near the other enda slot, u, ismade transversely through it. Through the oblong slot at a bar, 0, ispassed and secured in place against endwise displacement by means of avertical pin, I). By having several holes through the beam A forreceiving the pin I) the cross-bar C may be adjusted nearer to orfurther from the platform B, as circumstances require. Between thecrossbar 0 and the platform B two legs, D D, are attached, the lowerends of which are spread out so as to afford good firm supports. Thesides of the beam A are recessed at s s and rounded at o 0, and theimpinging ends of the legs D D present concave surfaces to the roundedsurfaces 0 0, and are confined thereto by a clamp-bolt, m. Thisattachment of the legs D D to the beam A allows the lower ends of thelegs to be spread apart more or less when the bolt m and braces c e areloosened.

Below the beam A, andapplied to the legs, are the braces e c, confinedtogether by means of a tube, f, and key g. These braces prevent thecasual spreading apart of the legs. For the purpose of lengthening thelegs extra pieces G G are employed, which are notched at i i to receivethe cross-bars of loops h h that are pivoted to the legs D D. Theseloops form strong attachments for the pieces G, and allow the latter tobe set higher or lower, as may be required. The beam A is furtherattached to the legs D D by means of the ties d d.

From the above description it will be seen that the improved jack can bepacked into a very small space by detaching the legs D D and cross-barG, in which condition it is very portable.

For outside work on buildings the jack is used in the following manner:The legs D D are secured to the beam A and adjusted the requireddistance apart so as to be received between the vertical portions of awindowframe, when these legs are supported upon the. sill of the frame.The bar 0 is then adjusted across the frame inside, and having beenpassed through its slot at, is secured by the pin 1), the cushions c cpressing against the frame. When thus adjusted the platform B willafford a perfectly safe support.

For inside work-such as for plastering and the like-the cross-bar G isdetached from the beam A and the platform-end of this beam is broughtagainst the wall, when a good support will be afforded for a scaffoldingor stage on which to stand while plastering or frescoing a ceiling orthe sides of a room, or for other purposes.

Having described my invention, I claim- The slotted platform-beam A, thecross-bar G, and the extensible legs D D, substantially as and for thepurposes described.

JOHN F. DARLEY.

Witnesses:

Ronr. LORTON, W. S. SMITH.

